However, Kamo hit right back through halfback Trent Dean off a quick tap 40 metres out.
OBM then took advantage of some back chat from the Kamo players to kick a penalty, but
Kamo came right back with a penalty of their own when OBM centre Rayden Anderson was sent to the sin bin.
Kamo capitalised on the numbers advantage when prop Mo Tukaki crashed over from close range.
This gave Kamo a 13-9 lead at the break.
However, they couldn't add any second half points against a resolute OBM defensive line.
OBM gave themselves a 10 point swing through a converted try and a penalty within a minute of each other.
This gave OBM a 19-13 lead with 25 minutes to play, meaning they couldn't rest on their laurels.
Try as they might though, Kamo couldn't find their way into OBM territory and build any sustained pressure.
Both sides were guilty at different times during the match of overplaying their hand and losing control of the ball.
Kapa broke the 23 minute stalemate with a late penalty goal to clinch the victory, sending the team and their fans wild.
In the Division One final, Kaihu staved off a spirited second-half effort from Southern to beat them 23-18.
Kaihu dominated in the first half, building a good lead.
However, Southern weren't going down without a fight, hitting back with tries early in the scond half.
Unfortunately for them, Southern left themselves too much to do and couldn't quite get the win in front of a highly passionate crowd.